1. Field of the Invention
The present invention relates to, in general, a windshield wiper for automobiles and, more particularly, to a wiper capable of reducing wind resistance, thereby being stably kept on the windshield.
2. Description of the Prior Art
As well known to those skilled in the art, a windshield wiper for automobiles is mounted to the lower portion of a windshield so as to selectively wipe the windshield.
An example of typical wipers for automobiles is referred to in Japanese Utility Model Publication No. 51-10498. The above wiper is schematically shown in FIGS. 5a and 5b.
As shown in FIGS. 5a and 5b, the wiper comprises a wiper frame 100 and two or more blade stays 107. The wiper frame 100, having a smoothly curved cross-section suitable for generating aerodynamic drag and lift, is connected to a wiper arm (not shown). The two stays 107 are connected to the wiper frame 100 at both side portions. The stays 107 individually have a V-shaped cross-section and are provided with vent holes 110 at positions around the center as best seen in FIG. 5b. A blade 115 is supported by the two stays 107. In order to connect the blade 115 to the stays 107, the blade 115 has a yoke part 116 holding the fitting parts of the stays 107.
However, the above Japanese wiper is problematic in that it may be unexpectedly lifted from the windshield when wind passes through the vent holes 110 of the stays 107.
Another example of typical wipers is referred to in Korean Utility Model Publication No. 93-14023 of the inventors of this invention. The above wiper is schematically shown in FIGS. 6a and 6b.
As shown in FIGS. 6a and 6b, the wiper 201 includes two longitudinal vent holes 203 with a spoiler 204 being provided at the edge of each vent hole 203. In order to form the above vent holes 203, the top wall of a wiper frame 202 is cut in three directions. That is, the top wall of the wiper frame 202 is cut along a U-shaped line at both side portions prior to bending the cut parts upwardly at an angle of inclination, thus forming two vent holes 203 and two spoilers 204. A side wall 206 is integrated with each end of the spoilers 204, thus closing the ends of the spoilers 204. The spoiler 204 helps to keep the wiper 201 on the windshield, thus preventing the wiper 201 from being unexpectedly separated from the windshield.
However, the above wiper 201 is problematic in that a vortex of air is formed around the side walls 206 and causes the wiper 201 to be unexpectedly separated from the windshield, thus making the wiper 201 lose its wiping function.
In addition, since the wiper frame 202 is cut so as to form both the vent holes 203 and the spoilers 204, the strength of the wiper 201 is reduced, thus causing the frame 202 to be easily deformed.
FIG. 6b is a sectional view of the wiper taken along the line 6b--6b of FIG. 6a. As shown in FIG. 6b, the wiper frame 202 has a generally U-shaped cross-section with a corner 205 being formed between each side wall and the top wall of the frame 202. The wind thus runs into the corner 205 when the wind is introduced into the wiper frame 202 and is upwardly discharged from the frame 202 through the vent holes 203. As a result, the wiper 201 may be unexpectedly separated from the windshield
Also, since the two spoilers 204 are upwardly protruded from the top wall of the wiper frame 202, the wiper arm is brought into contact with the top portion of one of the two spoilers 204 while mounting the wiper arm to the wiper frame 202. Such contact makes it difficult to mount the wiper arm to the wiper frame 202 and causes an interference between the spoilers 204 and the wiper arm during the operation of the wiper 201.